Related Experiment Video
Updated: Aug 18, 2026
Induced Differentiation of M Cell-like Cells in Human Stem Cell-derived Ileal Enteroid Monolayers
Published on: July 26, 2019
Toll-like receptor 2 is expressed on the intestinal M cells in swine
Masanori Tohno1, Takeshi Shimosato, Haruki Kitazawa
1Laboratory of Animal Products Chemistry, Graduate School of Agricultural Science, Tohoku University, Aobaku, Sendai 981-8555, Japan.
Abstract:
The Toll-like receptor (TLR) 2 binds a wide variety of microbial cell wall components. In this study, we investigated the expression pattern of TLR2 in adult swine gut-associated lymphoid tissues using real-time quantitative PCR, Western blotting, immunohistochemistry, and flow cytometric analysis. The mRNA for TLR2 was preferentially expressed in the mesenteric lymph nodes (MLNs) and Peyer's patches (Pps) of adult swine. Expression in these two tissues was approximately 15- and 9-fold higher than that of spleen, respectively. Western blotting further confirmed that the TLR2 protein was highly expressed in the MLNs and Pps. Interestingly, TLR2-expressing cells were found not only in immune cells, such as T cells and B cells, but also in membranous (M) cells. In addition, double immunostaining for TLR2 and cytokeratin 18 revealed that TLR2 was strongly expressed not only in the cytoplasm but also in the apical membrane of the pocket-like M cells. These results indicate that TLR2 on the MLNs and Pps enable the host defense to respond to a variety of cell wall components. Furthermore, the potential function of TLR2 as a pattern recognition receptor and its cellular distribution suggest that TLR2 plays an important role in ligand-specific transcytosis and transport in M cells.
Insights
Toll-like receptor (TLR) 2 is highly expressed in swine gut lymphoid tissues, particularly mesenteric lymph nodes and Peyer's patches. This suggests TLR2 plays a key role in host defense and transport processes within the gut.
Area of Science:
- Immunology
- Gastroenterology
- Microbiology
Background:
- Toll-like receptor (TLR) 2 recognizes diverse microbial cell wall components.
- Understanding TLR2 expression in swine gut-associated lymphoid tissues is crucial for host defense mechanisms.
Purpose of the Study:
- To investigate the expression pattern of TLR2 in adult swine gut-associated lymphoid tissues.
- To identify the specific cell types expressing TLR2 within these tissues.
Main Methods:
- Real-time quantitative PCR for mRNA expression.
- Western blotting for protein expression.
- Immunohistochemistry and flow cytometry for cellular localization.
Main Results:
- TLR2 mRNA and protein were preferentially expressed in mesenteric lymph nodes (MLNs) and Peyer's patches (Pps).
- Expression levels in MLNs and Pps were significantly higher compared to spleen.
- TLR2 was found on immune cells (T cells, B cells) and notably on membranous (M) cells, including their apical membrane.
Conclusions:
- TLR2 in swine MLNs and Pps contributes to host defense against microbial cell wall components.
- The cellular distribution of TLR2, especially on M cells, suggests a role in ligand-specific transcytosis and transport.
Related Concept Videos
01:23Renewal of Intestinal Stem Cells
01:12Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...